Metro Atlanta mayors and county commissioners on Thursday overcame decades of distrust to finalize a massive transportation project list that — if approved by voters — could bring relief to commuters in 10 counties.

The $6.14 billion in projects will go before voters in a referendum next year. There, residents will consider the project list along with a 10-year, 1% sales tax to fund it.

If approved at the ballot box, it would be the biggest single infusion of infrastructure dollars in the region in at least 40 years, prompting an avalanche of roadwork and new bus service in the first three years alone.